#!/bin/bash

source ScriptFunctions
Import File
Import GoboLinux
Import Log
Import OptionParser

### Options ###################################################################

scriptDescription="Install RPM packages on GoboLinux."
scriptCredits="Copyright (C) Lucas C. Villa Real, 2016 - Released under the GNU GPL."
helpOnNoArguments=yes
scriptUsage="<file.rpm>"
scriptExample="LibreOffice_5.2.3_Linux_x86-64_rpm"

Add_Option_Entry "l" "symlink" "If symlinks should be created and wether they should be forced on conflicts."  "yes" "yes no force"
Parse_Options "$@"

### Functions #################################################################

function uncompress_rpm() {
    local payload_compressor=$(rpminfo --compressor "$rpmfile")
    local cpiofile=$(basename "$rpmfile").cpio${payload_compressor:+.$payload_compressor}
    
    Log_Normal "Extracting RPM payload."
    rpm2cpio < "$rpmfile" > "$cpiofile"

    if [ "$payload_compressor" = "xz" ]
    then
        Log_Normal "Decompressing $payload_compressor payload."
        xz -d "$cpiofile"
        cpiofile=$(basename "$rpmfile").cpio
    fi

    Log_Normal "Extracting CPIO archive."
    cpio -d -i < "$cpiofile"
    rm -f -- "$cpiofile"
}

function flatten_rpm() {
    Log_Normal "Flattening directory structure."
    if [ -d "./usr" ]
    then
        cp -a ./usr/* .
        rm -rf -- ./usr
    fi
    if [ -d "./etc" ]
    then
        mkdir -p Resources/Defaults/Settings
        mv ./etc/* Resources/Defaults/Settings
        rm -rf -- ./etc
    fi
    if [ -d "./opt" ]
    then
        mkdir -p Resources/Unmanaged/opt
        if ls ./opt/* 2> /dev/null | grep -q "bin\|sbin\|lib\|lib64\|libexec\|include"
        then
            # 1-level dir: opt/pkgname/{bin,sbin,...}
            cp -va ./opt/*/* .
            for pkgdir in $(basename ./opt/*)
            do
                ln -s $goboIndex/ Resources/Unmanaged/opt/$pkgdir
            done
            realpath ./opt/* | sed "s,$(realpath $PWD),,g" >> Resources/UnmanagedFiles
        elif ls ./opt/*/* 2> /dev/null | grep -q "bin\|sbin\|lib\|lib64\|libexec\|include"
        then
            # 2-level dir: opt/vendorname/pkgname/{bin,sbin,...}
            # XXX needs testing
            cp -va ./opt/*/*/* .
            for vendordir in $(basename ./opt/*)
            do
                mkdir -p Resources/Unmanaged/opt/$vendordir
                for pkgdir in $(basename ./opt/*)
                do
                    ln -s $goboIndex/ Resources/Unmanaged/opt/$vendordir/$optdir
                done
            done
            realpath ./opt/*/* | sed "s,$(realpath $PWD),,g" >> Resources/UnmanagedFiles
        fi
        rm -rf -- ./opt
    fi
    if [ -d "./var" ]
    then
        mkdir -p Resources/Unmanaged/$goboVariable
        find ./var | sed "s,./var,$goboVariable,g" >> Resources/UnmanagedFiles
        mv ./var/* Resources/Unmanaged/$goboVariable
        rm -rf -- ./var
    fi
    rmdir * 2> /dev/null
}

function populate_resources() {
    local arch=$(rpminfo --arch "$rpmfile")
    local description=$(rpminfo --description "$rpmfile")
    
    Log_Normal "Populating Resources."
    mkdir -p Resources
    if [ "$arch" ] && [ "$arch" != "noarch" ]
    then
        echo "$arch" > Resources/Architecture
    fi
    if [ "$description" ]
    then
        cat /dev/null > Resources/Description
        echo "[Name] $(rpminfo --name $rpmfile)"               >> Resources/Description
        echo "[Summary] $(rpminfo --summary $rpmfile)"         >> Resources/Description
        echo "[License] $(rpminfo --license $rpmfile)"         >> Resources/Description
        echo "[Description] $(rpminfo --description $rpmfile)" >> Resources/Description
        echo "[Homepage] $(rpminfo --url $rpmfile)"            >> Resources/Description
    fi
}

function lookup_symbol() {
    local depname="$1"
    local testversion="$2"
    local arch="$3"
    local symbol="$4"
    local testarch=$(cat "$goboPrograms/$depname/$testversion/Resources/Architecture" 2> /dev/null)

    if [ "$testarch" ] && [ "$testarch" = "$arch" ]
    then
        Log_Verbose "Looking for symbol $symbol on $goboPrograms/$depname/$testversion/$path"
        if nm "$goboPrograms/$depname/$testversion/$path" 2> /dev/null | grep --max-count=1 -q "$symbol"
        then
            Log_Verbose "Match: $depname $testversion"
            echo "$depname $testversion"
            return 0
        fi
    fi
    return 1
}

function take_dependency_from_path() {
    local originalpath="$1"
    local path="$(echo $1 | sed 's,/usr,,g')"
    local symbol="$2"
    local fullpath="$(readlink -f $path)"
    local arch=$(rpminfo --arch "$rpmfile")
    local distro=$(rpminfo --distribution "$rpmfile")

    local depname=
    local depversion=

    if echo "$fullpath" | grep -q "^${goboPrograms}"
    then
        # If given, we search for the presence of @symbol on the given target file.
        # We iterate over different installations of the same program looking for
        # that symbol. If none of the installations have it, we fallback to printing
        # the dependency currently linked on /System/Index.
        #
        # Note that when iterating over installed programs we skip those entries whose
        # Resources/Architecture do not match the output of $(rpminfo --arch).

        depname=$(echo "$fullpath" | cut -d/ -f3)
        depversion=$(echo "$fullpath" | cut -d/ -f4)
        if [ "$symbol" ]
        then
            for testversion in $(ls $goboPrograms/$depname/ | grep -v "Settings\|Variable\|Current")
            do
                lookup_symbol "$depname" "$testversion" "$arch" "$symbol" && return 0
            done
        fi

        Log_Verbose "Fallback: $depname $depversion"
        echo "$depname $depversion"
    else
        # We have a path, but we don't have a link to that file under /System/Index.
        # Our first attempt is to search over the list of installed programs anyhow,
        # because some programs may not be currently activated.

        for fullpath in $(ls $goboPrograms/*/*/$path 2> /dev/null | grep -v "Current")
        do
            depname=$(echo "$fullpath" | cut -d/ -f3)
            testversion=$(echo "$fullpath" | cut -d/ -f4)
            [ -z "$depversion" ] && depversion="$testversion"
            Log_Verbose "Looking for symbol on candidate file $candidate ($depname, $testversion)"
            lookup_symbol "$depname" "$testversion" "$arch" "$symbol" && return 0
        done

        # We don't have a match. If we have a file name that satisfies the path but
        # that doesn't contain the requested symbol, we simply return that path.

        if [ "$depname" ] && [ "$depversion" ]
        then
            echo "$depname $depversion"
            return 0
        fi

        # We don't have a matching filename under /System/Index nor under /Programs/*/*.
        # What we do now is to query remote RPM databases to find which package hosts the
        # dependency file.

        Log_Normal "Searching the remote RPM database for the package hosting $originalpath"
        depname=$(RPMFinder --path="$originalpath" --arch="$arch" --distro="$distro")
        if [ "$depname" ]
        then
            # TODO: we could now lookup the GoboLinux recipe store to find whether we
            # have it or not
            echo "$(GuessProgramCase $depname)"
            return 0
        fi
    fi
}

function lookup_pkgname() {
    local dependency="$1"
    local pkgname=$(echo "$dependency" | cut -d'(' -f1)

    # Do we have a GoboLinux package installed with a matching name?
    for testname in $(ls $goboPrograms/*)
    do
        # Case-insensitive omparison (requires Bash 4)
        if [ "${testname,,}" = "{$pkgname,,}" ]
        then
            echo "$pkgname" && return 0
        fi
    done

    # Query the remote RPM database
    return 1
}

function is_basic_symbol() {
    local dependency="$1"
    echo "$dependency" | grep -q "^rtld("  && return 0
    return 1
}

function is_rpmlib_symbol() {
    local dependency="$1"
    echo "$dependency" | grep -q "^VersionedDependencies"  && return 0
    echo "$dependency" | grep -q "^PayloadFilesHavePrefix" && return 0
    echo "$dependency" | grep -q "^CompressedFileNames"    && return 0
    echo "$dependency" | grep -q "^PayloadIs"              && return 0
    return 1
}

function populate_dependencies_loop() {
    rpminfo --dependencies "$rpmfile" | while read dependency
    do
        if echo "$dependency" | grep -q "^/"
        then
            depinfo=$(take_dependency_from_path $dependency "")
            if [ "$depinfo" ]
            then echo "$depinfo"
            else echo "# Unresolved dependency: $dependency"
            fi
        elif echo "$dependency" | grep -q "^lib.*.so*"
        then
            libname=$(echo "$dependency" | cut -d'(' -f1)
            wantedsymbol=$(echo "$dependency" | cut -d'(' -f2 | cut -d')' -f1)
            depinfo="$(take_dependency_from_path $goboLibraries/$libname $wantedsymbol)"
            if [ "$depinfo" ]
            then echo "$depinfo"
            else echo "# Unresolved dependency: $dependency"
            fi
        elif is_basic_symbol "$dependency"
        then
            Log_Verbose "Skipping basic symbol: $dependency"
        elif is_rpmlib_symbol "$dependency"
        then
            Log_Verbose "Skipping internal symbol: $dependency"
        else
            depinfo=$(lookup_pkgname "$dependency")
            if [ "$depinfo" ]
            then echo "$depinfo"
            else echo "# Unresolved dependency: $dependency"
            fi
        fi
    done
}

function populate_dependencies() {
    Log_Normal "Processing dependencies."
    populate_dependencies_loop | sort -n | uniq
}

### Operation #################################################################

Is_Writable "${goboPrograms}" || Verify_Superuser

symlink="$(Entry symlink)"
rpmfile="$(readlink -f $(Arg 1))"
programname=$(rpminfo --name "$rpmfile")
programversion=$(printf "%s_%s" $(rpminfo --version "$rpmfile") $(rpminfo --release "$rpmfile"))

PrepareProgram -t "$programname" "$programversion"

# Update program name (PrepareProgram may have changed its case)
programname=$(ls $goboPrograms/ | grep -i "^${programname}$")
target="$goboPrograms/$programname/$programversion"

# Installation pipeline
Quiet pushd "$target" || Die "Could not enter $target"
uncompress_rpm
flatten_rpm
populate_resources
populate_dependencies
Quiet popd

# Symlinking
if [ "$symlink" = "no" ]
then
    Log_Normal "Done."
    exit 0
fi

[ -d "$target/Resources/Defaults/Settings" ] && UpdateSettings "$programname" "$programversion"
SymlinkProgram "$programname" "$programversion"
Log_Normal "Done."